The value of the expression [cosec (75° + θ) – sec (15° – θ) �

1.	The value of the expression [cosec (75° + θ) – sec (15° – θ) – tan (55° + θ) + cot (35° – θ)] is(A) – 1 (B) 0 (C) 1 (D) 3/ 2
Answer» (B) 0 According to the question, We have to find the value of the equation, cosec(75°+θ) – sec(15°-θ) – tan(55°+θ) + cot(35°-θ) = cosec[90°-(15°-θ)] – sec(15°-θ) – tan(55°+θ) + cot[90°-(55°+θ)] Since, cosec (90°- θ) = sec θ And, cot(90°-θ) = tan θ We get, = sec(15°-θ) – sec(15°-θ) – tan(55°+θ) + tan(55°+θ) = 0

The value of the expression [cosec (75° + θ) – sec (15° – θ) – tan (55° + θ) + cot (35° – θ)] is(A) – 1 (B) 0 (C) 1 (D) 3/ 2

Answer»

(B) 0

According to the question,

We have to find the value of the equation,

cosec(75°+θ) – sec(15°-θ) – tan(55°+θ) + cot(35°-θ)

= cosec[90°-(15°-θ)] – sec(15°-θ) – tan(55°+θ) + cot[90°-(55°+θ)]

Since, cosec (90°- θ) = sec θ

And, cot(90°-θ) = tan θ

We get,

= sec(15°-θ) – sec(15°-θ) – tan(55°+θ) + tan(55°+θ)

= 0